Flora of the Canadian Arctic Archipelago
Brassicaceae (Cruciferae), Draba family.
Published in In Franklin, Narr. Journey Polar Sea (Bot. App.) 743. 1823.
Type: Canada: Mackenzie Distr., "Barren Grounds from lat. 64° to Arctic Sea, in lat. 69°N". Richardson. Holotype: BM.
Synonymy. Cardamine hyperborea O.E.Schulz, nom. superfl., Bot. Jahrb. Syst. 32: 550. 1903.
Cardamine digitata Richardson var. oxyphylla Trautv., Trudy Imp. S.-Peterburgsk. Bot. Sada 6: 11. 1879
Cardamine hyperborea O.E.Schulz var. oxyphylla (Trautv.) O.E. Schulz, Bot. Jahrb. Syst. 32: 551. 1903.
Cardamine richardsonii Hultén, nom. superfl., Acta Univ. Lund., n. s., sect. 2, 41, 1: 838. 1945.
Vegetative morphology. Plants 9.5–20 cm high; perennial herbs. Only fibrous roots present. Ground level or underground stems horizontal; rhizomatous; elongate; 0.5–1 mm wide (fragile, and not always collected on herbarium specimens). Caudex absent. Aerial stems erect; not filiform. Leaves present; distributed along the stems; alternate; dying annually and non-persistent. Petioles present; 2.5–5.5(–15) mm long (to 15 mm long, CAN 61147); glabrous. Leaf blades compound. Blades 20–30(–40) mm long, 8–20 mm wide. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blade margins entire. Leaflet arrangement pinnate. Leaflets 3–5(–7); 10–20 mm long; 1.5–2.5(–3.5) mm wide; linear, or oblong; veins inconspicuous. Apical leaflet base not distinctly stipitate.
Reproductive morphology. Flowering stems conspicuously taller than the leaves; with leaves. Inflorescences racemose (densely flowered); 1–2 cm long (in flower, to 6 cm long in fruit); 10–20 mm wide (in flower). Pedicels present; glabrous. Flowers per inflorescence (3–)9–15; medium-sized; radially symmetrical (actinomorphic). Sepals conventional; 4; free; 1.5–2 mm long; 2.2–2.8(–3.3) mm wide; green and purple (green, usually purple-tipped). Calyx glabrous. Petals conventional; free; 4; white; without contrasting markings; obovate; unlobed; 5.5–6.5 mm long; (2.5–)3–5(–6) mm wide. Stamens 6; stamen filaments markedly unequal in length; stamen filaments glabrous. Anthers yellow; 0.6–1 mm long. Ovary superior; carpels 2; syncarpous. Ovaries oblong; glabrous. Styles 1; thick and short; 1 mm long. Stigmas per ovary 1. Placentation parietal. Ovules per ovary 10–16(–20). Fruit stalked (short-stipitate); dry; a silique; elongate-cylindrical; 20–35 mm long; 2 mm wide; glabrous; dehiscent; shedding the outer walls to expose a thin inner wall, with the seeds attached at the margins on either side. Styles remaining straight; persisting in fruit 2–3 mm long. Seeds 16–20; 2 mm long; brown; surfaces verrucose.
Chromosome information. 2n = 28, or 42.
2n (4x) = 28. Johnson and Packer (1968, northwestern Alaska); Zhukova (1969, northeastern Asia); Zhukova and Petrovsky (1971, 1972, Wrangel Island, 1984, eastern Chukotka); Zhukova et al. (1973 north and northeastern Asia.
2n (6x) = 42. Zhukova (1966, northeastern Asia); Zhukova and Petrovsky (1972, 1981, Wrangel Island); Zhukova et al. (1973, northern and northeastern Asia); Mulligan (2003).
Löve and Löve (1975) arbitrarily interpreted chromosome counts from Russian publications by sorting them according to ploidy levels. Actually, these data belong to three different species: C. digitata, C. hyperborea [C. microphylla subsp. blaisdellii], and C. microphylla [subsp. microphylla]. All three species have tetraploid and hexaploid races, and C. microphylla also has higher chromosome counts. (Petrovsky, personal communication, 2002, to Elven et al. 2003).
Ploidy levels recorded 4x and 6x.
Ecology and habitat. Substrates: wet meadows, along streams, river terraces, slopes, ridges; imperfectly drained moist areas, seepage slopes; rocks, sand, moss; with low organic content, with high organic content; acidic, or nitrophilous.
North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut. Range in the Canadian Arctic Archipelago limited. Uncommon. Low Arctic. Arctic islands: Banks, Victoria, Prince of Wales, Southampton.
Northern hemisphere distribution. Amphi-Beringian. West Chukotka, Wrangel Island, East Chukotka, West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay.
General notes. This species is unproblematical, even if the names that have been applied have been widely discussed (see Elven et al. 2003).
Elven et al. (2005) supplied the following information.
Cardamine digitata Richardson. "This characteristic plant was described from northwestern Canada: Mackenzie district. The name is unambiguous, as only one entity of the aggregate occurs in that area. Trautvetter (1879) and Schulz (1903) misunderstood this plant (see below). Their var. oxyphylla of either C. digitata or C. hyperborea refers to C. digitata s.s."
Cardamine hyperborea O.E. Schulz. "This name has been applied differently among authors. Schulz (1903) coined the name as a direct substitute of C. digitata Richardson, which he assumed was a later homonym of Cardamine digitata Lamarck (1786). However, Lamarck described his species as Dentaria digitata, not as a Cardamine. Cardamine hyperborea is therefore based on the same type as C. digitata and is a superfluous synonym, as already pointed out by Shetler (1961) and Rollins (1993) and confirmed by Egorova (in a personal communication to Elven, 2004): "Cardamine hyperborea is a nomen superfluvum illegitimum [for C. digitata Richardson] according to Art. 52, 1–52.2 of the St. Louis Code"."
Cardamine richardsonii Hultén. "Hultén (1945) coined this name to replace C. digitata Richardson, as he also, on the authority of Schulz, erroneously assumed that Richardson's name was predated by Lamarck's 'digitata' and that C. hyperborea belonged to the broad-leaved plants. Löve and Löve (1975) followed the same approach. Hultén's name is also a superfluous, full synonym of C. digitata."
Illustrations. • Habitat. Plants growing between the markers in an Eriophorum vaginatum meadow. N.W.T., Tuktoyaktuk. 9 August, 2001. Aiken and Brysting 01–019. CAN. • Habitat. Plants growing between the markers at the base of an Eriophorum vaginatum tussock. Leaves bright green, whitish flower and bud. N.W.T., Tuktoyaktuk. 9 August, 2001. Aiken and Brysting 01–019. CAN. Scale bar in cm. • Close-up of plants in habitat. Plants in lush moist tundra. N.W.T., Banks Island, Parker River valley. August, 1999. Photograph by R. Elven. Voucher at 0. • Plant habit. Plants growing in a sheltered gully. Note the pinnate leaves that have crowded leaflets, therefore being almost digitate. N.W.T., Banks Island, Sachs Harbour. 27 July, 1981. J.M. Gillett 18854. CAN. • Close-up of leaves. Compound leaves with pinnate leaflets. These leaflets are often crowded, appearing almost digitate (palmate), giving the origin of the species name. N.W.T. Tuktoyaktuk. 9 August, 2001. Aiken and Brysting 01–019. CAN. • Close-up of plant. Racemose flowering stem. Note the cream-coloured and swollen gynophore (stalk joining the gynoecium to the receptacle). Some of the fruits are developing into siliques which are much longer than wide and have the remains of a sessile stigma. N.W.T., Tuktoyaktuk. 9 August, 2001. Aiken and Brysting 01–019. CAN. • Herbarium specimen. Left stem, late stages of flowering. Right stem, early stage of fruiting. Yukon, Ogilvie Mountains. 3 July, 1968. R.T. Porsild. CAN 318583. • Arctic Island Distribution.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..